A widely used storage medium for storing information is storage tape, such as magnetic tape. Storage tapes can be mounted in various types of tape cassettes or cartridges. One type of tape cassette or cartridge is a two-reel or two-spindle cassette or cartridge in which the tape is housed entirely within the cassette or cartridge. One end of the tape is attached to a first reel, while another end of the tape is attached to a second reel. The cassette or cartridge is loaded into a tape drive, which includes a tape head assembly that engages the tape to read data from or record data to the tape as the tape is wound from one reel to the other in the tape cassette or cartridge.
Alternatively, a single-reel or single-spindle tape cartridge can be used in which the cartridge has one reel or spindle. In a single-reel design, the source reel is located in the tape cartridge, but a take-up reel is located outside the cartridge in the tape drive. When the single-reel cartridge is loaded into the tape drive, an end of the tape is removed from the cartridge and loaded onto the take-up reel of the tape drive.
To achieve increased data transfer rates, tape drives employ tape head assemblies having multiple channels of read and write elements. A write element of the tape head includes a thin-film inductive element for recording data, while the read element is a magnetically sensitive thin-film resistive element for detecting data bits. Multiple channels of write elements are capable of recording to multiple data tracks of the tape simultaneously, and multi-channel read heads are capable of reading from multiple data tracks of the tape simultaneously. In one example, a tape head assembly can have 16 channels, with 8 channels for recording to or reading data from the tape as the tape moves in a first direction, and 8 channels for recording to or reading from the tape as the tape moves in the opposite direction. In conventional tape drives, each channel is associated with a dedicated write driver and read amplifier. If a tape head assembly includes a large number of channels, then the amount of circuitry (write drivers and read amplifiers) required to perform read and write tasks can be quite large.
Another issue associated with tape head assemblies is the presence of electrical interference or crosstalk between write and read elements, as well as between the write and read signal paths or traces electrically connected to respective write and read elements. Crosstalk between write elements (and traces) and read elements (and traces) typically result from the presence of relatively high currents in the write elements and write traces when recording data to tape. Also, reduction in the size of tape head assemblies has further increased the likelihood of crosstalk between write and read elements (and traces) that are placed in closer proximity to each other.